polymyxin E

drug

Also known as: colistin

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Last updated

July 1, 2026

Quick Summary

Polymyxin E, also known as colistin, is a polypeptide antibiotic derived from soil bacteria of the genus Bacillus. It is effective against gram-negative bacteria, such as Escherichia coli and Pseudomonas aeruginosa, by disrupting their cell membranes.12

Polymyxin E is used clinically, particularly for treating infections resistant to other antibiotics. It is sometimes administered via intramuscular injection and is frequently used to treat diarrhea in children. However, polymyxins can also affect human cell membranes, potentially causing kidney damage and neurotoxicity, which limits their use when other antibiotics are available.1

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polymyxin
Only polymyxins B and E are used clinically. Their chief therapeutic use is in the treatment of infections involving gram-negative bacteria that are resistant to penicillin and other broad-spectrum antibiotics. Polymyxin B is applied topically to treat infections such as those of the eye, the ear, the skin, and…
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Only polymyxins B and E are used clinically. Their chief therapeutic use is in the treatment of infections involving gram-negative bacteria that are resistant to penicillin and other broad-spectrum antibiotics. Polymyxin B is applied topically to treat infections such as those of the eye, the ear, the skin, and…
Read More